Unused Symbol: Check descriptor before creating light class to prevent InvalidMirrorException on red code

idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/resolutionApi.kt

@@ -29,7 +29,10 @@ import org.jetbrains.kotlin.psi.JetDeclaration
 import org.jetbrains.kotlin.psi.JetElement
 import org.jetbrains.kotlin.psi.JetFile
 import org.jetbrains.kotlin.psi.JetPsiFactory
-import org.jetbrains.kotlin.resolve.*
+import org.jetbrains.kotlin.resolve.BindingContext
+import org.jetbrains.kotlin.resolve.BindingTraceContext
+import org.jetbrains.kotlin.resolve.ImportPath
+import org.jetbrains.kotlin.resolve.QualifiedExpressionResolver
 import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
 import org.jetbrains.kotlin.resolve.lazy.FileScopeProvider
 import org.jetbrains.kotlin.resolve.lazy.LazyFileScope
@@ -42,6 +45,10 @@ public fun JetDeclaration.resolveToDescriptor(): DeclarationDescriptor {
     return getResolutionFacade().resolveToDescriptor(this)
 }
 
+public fun JetDeclaration.resolveToDescriptorIfAny(): DeclarationDescriptor? {
+    return analyze(BodyResolveMode.PARTIAL).get(BindingContext.DECLARATION_TO_DESCRIPTOR, this)
+}
+
 public fun JetFile.resolveImportReference(fqName: FqName): Collection<DeclarationDescriptor> {
     val facade = getResolutionFacade()
     return facade.resolveImportReference(facade.moduleDescriptor, fqName)

idea/src/org/jetbrains/kotlin/idea/highlighter/KotlinTestRunLineMarkerContributor.kt

@@ -26,13 +26,11 @@ import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.asJava.KotlinLightClass
 import org.jetbrains.kotlin.asJava.toLightClass
 import org.jetbrains.kotlin.asJava.toLightMethods
-import org.jetbrains.kotlin.idea.caches.resolve.analyze
+import org.jetbrains.kotlin.idea.caches.resolve.resolveToDescriptorIfAny
 import org.jetbrains.kotlin.psi.JetClassOrObject
 import org.jetbrains.kotlin.psi.JetNamedDeclaration
 import org.jetbrains.kotlin.psi.JetNamedFunction
 import org.jetbrains.kotlin.psi.psiUtil.getStrictParentOfType
-import org.jetbrains.kotlin.resolve.BindingContext
-import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
 import javax.swing.Icon
 
 class KotlinTestRunLineMarkerContributor : RunLineMarkerContributor() {
@@ -47,8 +45,7 @@ class KotlinTestRunLineMarkerContributor : RunLineMarkerContributor() {
         if (declaration.nameIdentifier != element) return null
 
         // To prevent IDEA failing on red code
-        if (declaration.analyze(BodyResolveMode.PARTIAL)
-                .get(BindingContext.DECLARATION_TO_DESCRIPTOR, declaration) == null) return null
+        if (declaration.resolveToDescriptorIfAny() == null) return null
 
         val project = element.project
 

idea/src/org/jetbrains/kotlin/idea/highlighter/markers/SuperDeclarationMarker.kt

@@ -28,6 +28,7 @@ import org.jetbrains.kotlin.descriptors.PropertyAccessorDescriptor
 import org.jetbrains.kotlin.descriptors.PropertyDescriptor
 import org.jetbrains.kotlin.idea.JetBundle
 import org.jetbrains.kotlin.idea.caches.resolve.analyze
+import org.jetbrains.kotlin.idea.caches.resolve.resolveToDescriptorIfAny
 import org.jetbrains.kotlin.idea.codeInsight.DescriptorToSourceUtilsIde
 import org.jetbrains.kotlin.idea.codeInsight.JetFunctionPsiElementCellRenderer
 import org.jetbrains.kotlin.psi.JetDeclaration
@@ -112,8 +113,7 @@ public data class ResolveWithParentsResult(
         val overriddenDescriptors: Collection<CallableMemberDescriptor>)
 
 public fun resolveDeclarationWithParents(element: JetDeclaration): ResolveWithParentsResult {
-    val bindingContext = element.analyze()
-    val descriptor = bindingContext.get(BindingContext.DECLARATION_TO_DESCRIPTOR, element)
+    val descriptor = element.resolveToDescriptorIfAny()
 
     if (descriptor !is CallableMemberDescriptor) return ResolveWithParentsResult(null, listOf())
 

idea/src/org/jetbrains/kotlin/idea/inspections/UnusedSymbolInspection.kt

@@ -42,6 +42,8 @@ import org.jetbrains.kotlin.asJava.LightClassUtil
 import org.jetbrains.kotlin.asJava.toLightClass
 import org.jetbrains.kotlin.descriptors.annotations.Annotated
 import org.jetbrains.kotlin.idea.JetBundle
+import org.jetbrains.kotlin.idea.caches.resolve.analyze
+import org.jetbrains.kotlin.idea.caches.resolve.resolveToDescriptorIfAny
 import org.jetbrains.kotlin.idea.findUsages.KotlinFindUsagesHandlerFactory
 import org.jetbrains.kotlin.idea.findUsages.handlers.KotlinFindClassUsagesHandler
 import org.jetbrains.kotlin.idea.search.usagesSearch.*
@@ -52,7 +54,9 @@ import org.jetbrains.kotlin.psi.psiUtil.getElementTextWithContext
 import org.jetbrains.kotlin.psi.psiUtil.getNonStrictParentOfType
 import org.jetbrains.kotlin.psi.psiUtil.getParentOfType
 import org.jetbrains.kotlin.psi.psiUtil.isAncestor
+import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.DescriptorUtils
+import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
 import org.jetbrains.kotlin.types.expressions.OperatorConventions
 import org.jetbrains.kotlin.utils.singletonOrEmptyList
 import java.awt.GridBagConstraints
@@ -159,6 +163,7 @@ public class UnusedSymbolInspection : AbstractKotlinInspection() {
                 if (declaration is JetNamedFunction && isConventionalName(declaration)) return
 
                 // More expensive, resolve-based checks
+                if (declaration.resolveToDescriptorIfAny() == null) return
                 if (isEntryPoint(declaration)) return
                 if (declaration is JetProperty && declaration.isSerializationImplicitlyUsedField()) return
                 if (isCompanionObject && (declaration as JetObjectDeclaration).hasSerializationImplicitlyUsedField()) return

idea/testData/inspections/unusedSymbol/class/BadCodeNoExceptions.kt

@@ -0,0 +1,6 @@
+// Closing brace is intentionally missed
+val id = array("kotlin.FlexibleType"
+
+private class Some() {
+    override fun foo() = 1
+}

idea/testData/inspections/unusedSymbol/class/inspectionData/expected.xml

@@ -47,4 +47,12 @@
     <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Unused Symbol</problem_class>
     <description>Class 'B' is never used</description>
   </problem>
+  <problem>
+    <file>BadCodeNoExceptions.kt</file>
+    <line>2</line>
+    <module>light_idea_test_case</module>
+    <entry_point TYPE="file" FQNAME="temp:///src/badCodeNoExceptions.kt" />
+    <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Unused Symbol</problem_class>
+    <description>Property 'id' is never used</description>
+  </problem>
 </problems>